Key Stone and Foundation Species

1. Discuss with your team the meaning of and difference between these two ecosystem organisms.

2. THEN – Create a T-chart categorizing the following species into its proper group AND brief explanation why.

• Coral Elephant Hummingbird• Kelp Mountain lion Sea star• Prairie dog Sea otter Trees

Key Stone Species – organism that plays a crucial role ecosystem functions. Without it - ecosystem would be dramatically different or cease to exist .

keystone species in tide pools: eat sea urchins, mussels, and other shellfish that have no other natural predators.

Contributes to the existence of the ecosystem in which it lives. Contribute to the soil and water quality in their plains ecosystem. Their foraging retains water in the soil and forces fresh new grasses to continually grow.

In savannas - without the presence of elephants, grasslands would develop into forests.

Kelp, a giant species of seaweed, is home to hundreds of species, from sea stars to sharks. Sea urchins eat kelp. Sea otters eat sea urchins, preventing an overpopulation of urchins from destroying the ecosystem.

In deserts - Hummingbirds pollinate many varieties of native cactus and other plants. In deserts with few hummingbirds, invasive species such as have taken over the ecosystem.

Keystone species are often predators, like this mountain lion. The deer, rabbits, and bird species in the ecosystem are at least partly controlled by the presence of the mountain lion. Their feeding behavior, or where they choose to make their nests and burrows, is largely a reaction to the mountain lion’s activity.

Key Stone Species

Endangered

Endangered

Threatened

Threatened

Foundation species• “engineers of ecosystems.”• Build and maintain habitats that benefit other

organisms that use .

harvest trees, thus removing undergrowth and maintaining an open forest understory.

Corals build coral reefs that many other species use.

kelp provide shelter and habitat for other organisms in ocean.